gib: overlay module for on-chain git commit heads

[shruggr]

Summary

New overlay module for gib (on-chain git): indexes commit heads, the 1-sat PushDrop coins with fields ["gib", origin, branch, root, identity] that carry the git commit object as an inscription. A coin's spend chain is the branch's push history, so each head is stored with its decoded commit and linked to the head it spent.

• pkg/template/gib — decoder (lock-before/after, inscription prefix/suffix, raw or txid_vout outpoints, raw or hex identity), git commit parser with object id, reference encoder.
• pkg/gib — topic tm_gib, lookup ls_gib, gib_heads table (SQLite/Postgres), REST under /1sat/gib (/repos, /identity/:id/repos, /repo/:origin, /repo/:origin/branches, /repo/:origin/branch/*, /heads, /head/:outpoint), BRC-24 lookup, SpendSync for burns, README + swagger fragment.
• pkg/parse/gib.go — emits gib and gib:{origin} events (per-repo SSE feed for free).
• cmd/server — init, status-handler lookups, admin engines, routes, event bridge gib/spend:gib → q:gib (single worker, arrival order), optional JungleBus subscriber, runtime keys overlay.gib.*, admin UI panel.

Disabled by default (gib.mode: embedded or overlay.gib.enabled to turn on). Feeds from broadcasts through the stack; no JungleBus subscription required.

Consumer: gibhub.net. Design docs: gib-cli docs/plans/.

Test plan

• go test ./pkg/template/gib ./pkg/gib ./pkg/parse ./cmd/server (decode variants/rejects, commit parsing vs git hash-object, mint → push → burn linking, spend-before-admit, block-height restamp, eviction, BRC-24 queries, REST routes, runtime config)
• go build ./... && go vet; admin UI tsc -b
• Smoke against a running stack once the CLI publishes real heads with the final field encoding (the decoder accepts both string and binary outpoints; confirm against the SDK PR)

🤖 Generated with Claude Code

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